You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Migrating a managed Photo library on external drive to a new Mac?

I have my Photos library on an external drive, with all originals downloaded into the library on the external drive. What's the process for migrating that external drive library to a new Mac? Can I just plug in the external drive into the new Mac and make it the System Photo library? Will that keep all files on the external drive in tact, without modification? I have a specific backup system that I've been using and don't want the migration to mess it up. I don't want Photos to re-download and overwrite all of the photos/files already on my external drive. Any idea if that will happen??

Mac mini, macOS 10.15

Posted on Jan 26, 2023 5:30 AM

Reply
Question marked as Top-ranking reply

Posted on Jan 26, 2023 8:51 AM

The pictures are stored in the Photos Library, and that's what you have on your external drive, right? This library can be read by any Photos app from the same or newer OS. BUT, for a newer OS, Photos will re-write its database to take advantage of new features. That means that once you use, say, Ventura, to read the Catalina library, then Catalina will no longer be able to access it, since Catalina doesn't know about the new database.


The Unmodified Originals in the library will always be unmodified-- they can be exported unchanged to Finder anytime. Edits and keywords that you have added will also be intact when you export edited copies. Photos doesn't store edited pictures-- its database stores a record of the adjustments that were made, and it applies those on the fly when you look at them. Really, the pictures will all be the same. Not to worry!


That said, if I were you, I would make a copy (option -drag) of the library in a separate folder. Backups relieve a lot of tension. Then you just plug in the external drive and double click on the library.


Also, keep in mind: To get full functionality (and to avoid damaging the Photos Library) an external drive must be formatted in either APFS format or Mac OS Extended (Journaled) format. Additionally, the drive can not have had Time Machine on it since it was formatted.

Move your Photos library to save space on your Mac - Apple Support


You may have gotten away with a non-Mac format in the past, but it would cause lots of trouble in the future. We've seen lots of that.


We upgrade to new OSs all the time-- it works.

Similar questions

4 replies
Question marked as Top-ranking reply

Jan 26, 2023 8:51 AM in response to lnjustin

The pictures are stored in the Photos Library, and that's what you have on your external drive, right? This library can be read by any Photos app from the same or newer OS. BUT, for a newer OS, Photos will re-write its database to take advantage of new features. That means that once you use, say, Ventura, to read the Catalina library, then Catalina will no longer be able to access it, since Catalina doesn't know about the new database.


The Unmodified Originals in the library will always be unmodified-- they can be exported unchanged to Finder anytime. Edits and keywords that you have added will also be intact when you export edited copies. Photos doesn't store edited pictures-- its database stores a record of the adjustments that were made, and it applies those on the fly when you look at them. Really, the pictures will all be the same. Not to worry!


That said, if I were you, I would make a copy (option -drag) of the library in a separate folder. Backups relieve a lot of tension. Then you just plug in the external drive and double click on the library.


Also, keep in mind: To get full functionality (and to avoid damaging the Photos Library) an external drive must be formatted in either APFS format or Mac OS Extended (Journaled) format. Additionally, the drive can not have had Time Machine on it since it was formatted.

Move your Photos library to save space on your Mac - Apple Support


You may have gotten away with a non-Mac format in the past, but it would cause lots of trouble in the future. We've seen lots of that.


We upgrade to new OSs all the time-- it works.

Jan 26, 2023 8:58 AM in response to lnjustin

When you want to use the library on a new Mac, ist is essential to set the "Ignore Ownership on this volume" flag for the volume on he external drive where the library is located. Otherwise you may encounter ownership issues when you try to open the library on your new Mac. How to set this flag is described in the link proved by Richard: Move your Photos library to save space on your Mac - Apple Support

Jan 26, 2023 9:13 AM in response to lnjustin

Internally, the pictures actually have different file names than you expect. I must have at least 7 pictures with the original file name IMG_0011, or something like that. So Photos renames them, but stores the original file name in its database. This works great, is completely transparent, and has never been a problem. And, by the way, Photos started doing this with Catalina, so your pictures are already in this state.


You are good to go. You should make a backup, anyway. 😏

Migrating a managed Photo library on external drive to a new Mac?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.